Retarded release stop



Sept. 27, 1932. c. Q FARMER 1,879,670

RETARDED RELEASE STOP Filed Nov. 13, 1950 23 E ATTORNEY.

Patented Sept. 27,y 1932 UNITED STATES orFIiCe c LYDE c. FARMER, 0E PITTSBURGH, PENNSYLVANIA, AsSIGNoR To TIIE WESTING- y HOUSE AIR BRAKE COMPANY, 0E WILMERDING, PENNsYLvANIA, A CORPORATION OF PENNSYLVANIA RETARDED RELEASE. STOP Application filed November 13, 1930.V SerialNo. 495,397. Y

This invention relates to fluid pressure brakes, and more particularly to a retarded release stop device, as employed in a triple valve device having the retarded release feature, such, for example, as that disclosed in Patentl No. 1,055,373, of Walter V. Turner, issued March 11, 1913.

It has been proposed to associate with the piston stem of a retarded release triple valve device, a yielding stop device for controlling the quick service action of the triple valve device.

This yielding stop device is disposed at the rear end of the triple piston stem, and is such that the usual retarded release stop cannot be employed.

The principal object of my invention is to provide a retarded release stop device adapted to be employed in connection with a triple valve device of the above character.

In the accompanying drawing: Fig. 1 is a sectional view of a retarded release triple valve device embodying my invention; Fig. 2 an enlarged detail view of the retarded release stop casing; Fig. 3 a section on the line 3 3 of Fig. 2; and Fig. 4 an enlarged section of the rear portion of the triple valve device shown in Fig. 1, showing the yielding stop mechanism, associated with the triple piston Stem, in section.

The triple valve device shown in Fig. 1, comprises a casing 1, having a piston chamber 2, which communicates with a passage 3, leading to the brake pipe (not shown) and containing a piston 4 and having a valve chamber 5, communicating through an opening 6 in a cap 7 with the usual auxiliary reservoir (not shown) and containing a main slide valve 8 and a graduating slide valve 9, mounted on and having a movement relative to the main slide valve. The valves 8 and 9 are operated by piston 4, through a piston stem 10.

Carried at the rear end of piston stem 10 is a cylindrical casing 11 in which is mounted a spring stop member 12. Said member is subject to the pressure of a coil spring 18 mounted in the casing 11 and is provided with a forwardly projecting stem 14 adapted to engage the inner endfoiithe main slide valve 8. Q

I According to my invention, a' retarded .re-v lease stop device is provided, which is adapted to be employed, V,when the triple valve device carries :at the rear end of the triple piston stem, ayielding stop device as above v described.

The retarded release Stop device comprises a generally cylindrical casing 16, the forward end of which is adapted to engage the rear end of the main slide valve 8. YAt the inner end, the casing 16 is provided with an annular `raised portion 17 `which acts as a guide in the slide valve. bushing 18'and at the outer end, the casing is provided with an annular raised portion 19 which acts as a guide Tin the capV 7 Intermediate its ends, the casing 16 is pro'- vided lwith an internal .collar 20 which. engages and acts as a guide for the casing 11 carried by the piston stem 10, and the casing 11 is provided with a collar 21, which is adapte'dvto engage-the collar 20, when the triple valve piston v4 is in normal release position. A plurality of longitudinal grooves 22 are milled in the casing, to provide cominunicationfor the flow of fluid under pres-V sure between lthe valve chamber 5 and the auxiliary reservoir. A shoulder 23 of the casing 16 is adapted to'e'ngagethe end of the slide valve bushing 18, to define the normal release position of the retardedv release stop. A retardingcoil spring 24 is interposed between the wall 25 of the cap 7 and the collar 20 and yieldingly-resists inward movement of thecasing 16. l VheII the brake pipe pressure is reduced to effect anV application of the brakes, the piston 4 moves out from release position to brake application position', the casing 11 sliding in the internal guide .collar 2O. The outward movement of the retardedlrelease casing 16 is prevented by engagement of the shoulder 23 with the Vinner end of the bushing 18. When the brake pipe pressure is increased to effect the release of the brakes, the triple valve piston 4 is moved toward release position. If the increase in brake pipe pressure is gradual, as is the case on cars at the rear end of the train, if

' guide bearing working in said cap, and'said sleeve having a guide bearing for said casing the triple valve pistonmoves only to the normal release position, as shown in Fig. 1, further inward movement being prevented by the engagement of the collar 2'1 with the collar 20 of the retarded release stop device. When the increase in brake pipe pressureV is at a high rate, as on cars at the head end of the train, the triple valve piston 4 is moved toits inner retardedl release position, the casing 16 being moved inwardly, against the resistance of the retarding spring 24.

While one illustrative embodiment of the invention has been described in detail, iig-is, e 'not my intention to limit its scope to that vem, l' p t v bodiment or otherwise than by the terms of the appended claims. i

Having now described my invention, what I claim as new and desire to secure byfLetters Patent, is: Y Y

1. A triple valve device comprising valves, a piston having a piston stem foroperating said valves, a bushing in which said valves are mounted, a casing carried at the rear end of said stem, and a retarded release stop devicefor opposingV movement of said piston from normal release position to an inner retarded release position and comprising a sleeve in which said casing is mounted, said sleeve having a bearing ring engaging in said bushing, and having 'an internal,iinwardly projecting collar within which said casing is slidably mounted, a collar carried by said casing and adapted to engage the inwardly projecting collar, and a spring for. opposing movement of said sleeve from the normal release position to the inner retarded release position.

- 2. A triple valve device comprising a casing having a valve chamber, a valve in said chamber, a bushing having a valve seat for said valve, a piston, and a piston stem for operating said valve, a cylindrical casing carried at the rear end of said stem, and-a lretarded release stop device comprising a sleeve having a guide bearing working in saidbushv ing, a cap closing the-.valve chamber end of said triple valve casing, said sleevefhaving a and having a portion engageableby a portion of said casing to oppose movement of said casing and piston stem from normal release position to an inner retardedrelease position,

anda spring for opposing inward movement of said sleeve. Y

, In testimony whereof I have hereunto set my hand, this 10th day of November, 1930.

CLYDE C. FARMER. 

